The results from the above mentioned time-resolved spectral fitting are shown in Fig. REF  and are tabulated in Table REF . Note that the error bars shown in Fig. REF  represent 2\(\sigma \)  errors. This clearly shows that the spectral parameters, namely \(\Gamma \)  and log \(\xi \)  derived for both E1 and E2 show a hint of variation within 2\(\sigma \)  significance. \(\Gamma \)  shows an overall softening from epoch E1 to E2. On the other hand, the lamp-post height (h) is almost invariable during both epochs (E1 & E2) within 2\(\sigma \)  uncertainties. When we compare the spectral parameters obtained from time-resolved spectrum fitting and average spectrum fitting, we see that there is some variation in the values of \(\Gamma \)  and log \(\xi \) . Some \(\Gamma \)  values are above the average values, whereas the log \(\xi \)  values are below the average value. This variation in \(\Gamma \)  and log \(\xi \)  could be due to the difference in the energy range between the average spectrum and the time-resolved spectrum. For the average spectrum, we performed a fit in the energy range 0.5–79.0 keV, whereas we carried out time-resolved spectrum fitting in the energy range 3.0–79.0 keV, as we do not have Swift/XRT data for each time interval. A systematically lower log \(\xi \)  corresponds to a larger \(\Gamma \)  to produce a similar fit. These two parameters are anti-correlated to some degree and hence, if \(\Gamma \)  systematically increases, the ionization parameter will decrease [1]}, [2]}.
